import java.util.Arrays;

public class Test {
    class Solution {
        public int triangleNumber(int[] nums) {
            Arrays.sort(nums);
            int ret = 0;
            for(int i = nums.length - 1;i >= 0;i -- ) {
                int left = 0;
                int right = i-1;
                while(left < right) {
                    if(nums[left] + nums[right] > nums[i]) {
                        ret += right - left;
                        right --;
                    }else {
                        left ++;
                    }
                }
            }
            return ret;
        }
    }
}
